queue

Creates queue using Data structure concept

Author: Kundan-pseudo

queue

@@ -0,0 +1,100 @@
+#include<stdio.h>   
+    #include<stdlib.h>  
+    #define maxsize 5  
+    int front = -1, rear = -1;  
+    int queue[maxsize];  
+  
+    void insert()  
+    {  
+        int item;  
+        printf("\nEnter the element\n");  
+        scanf("\n%d",&item);      
+        if(rear == maxsize-1) 
+        {  
+            printf("\nOVERFLOW\n");  
+            return;  
+        }  
+        if(front == -1 && rear == -1)  
+        {  
+            front = 0;  
+            rear = 0;  
+        }  
+        else   
+        {  
+            rear = rear+1;  
+        }  
+        queue[rear] = item;  
+        printf("\nValue inserted ");  
+          
+    }  
+    void delete()  
+    {  
+        int item;   
+        if (front == -1 || front > rear)  
+        {  
+            printf("\nUNDERFLOW\n");  
+            return;  
+                  
+        }  
+        else  
+        {  
+            item = queue[front];  
+            if(front == rear)  
+            {  
+                front = -1;  
+                rear = -1 ;  
+            }  
+            else   
+            {  
+                front = front + 1;  
+            }  
+            printf("\nvalue deleted ");  
+        }  
+          
+          
+    }  
+          
+    void display()  
+    {  
+        int i;  
+        if(rear == -1)  
+        {  
+            printf("\nEmpty queue\n");  
+        }  
+        else  
+        {   printf("\nprinting values .....\n");  
+            for(i=front;i<=rear;i++)  
+            {  
+                printf("\n%d\n",queue[i]);  
+            }     
+        }  
+    }  
+    void main ()  
+    {  
+        int choice;   
+        while(choice != 4)   
+        {     
+            printf("\n*************************Main Menu*****************************\n");  
+            printf("\n=================================================================\n");  
+            printf("\n1.insert an element\n2.Delete an element\n3.Display the queue\n4.Exit\n");  
+            printf("\nEnter your choice ?");  
+            scanf("%d",&choice);  
+            switch(choice)  
+            {  
+                case 1:  
+                insert();  
+                break;  
+                case 2:  
+                delete();  
+                break;  
+                case 3:  
+                display(); 
+                break;  
+                case 4:  
+                exit(0);  
+                break;  
+                default:   
+                printf("\nEnter valid choice??\n");  
+            }  
+        }  
+    }